Internal Boeing messages released this month that showed employees boasting about pressuring regulators into accepting less training for the 737 Max were "unacceptable," CEO David Calhoun told CNBC on Wednesday.
"My stomach turned," he said on CNBC's "Squawk Box," after Boeing reported its first annual loss since 1997, a dismal result from the fallout from last year's 737 Max grounding. "The language is horrible" in those messages.
Boeing released more than 100 pages of internal messages on Jan. 9.
In the communications, provided to the Federal Aviation Administration, lawmakers and the public, employees talked about pushing regulators and airlines — including Lion Air, the carrier whose 737 Max first crashed in October 2018 — to approve the new planes without requiring pilots to undergo simulator training. Other workers raised safety concerns and complained about lax standards.
The messages were from a time period before the two deadly crashes of 737 Max jets, which led global regulators to ground the entire fleet last March after the second crash, which involved an Ethiopian Airlines plane. The two crashes killed a total of 346 people.
"We found out way too late," he added. "There was only one moment in time that if we had found out, we all would have done something. That is the day it was written."
"I can't rewrite history. I wish I could," he said.
In one of the messages, from April 2017, one Boeing employee told another, "This airplane is designed by clowns who in turn are supervised by monkeys."
Another showed a Boeing employee hopeful they could "gang up" on regulators and steer them "in the direction we want."
Boeing, earlier this month, said the messages "do not reflect the company we are and need to be, and they are completely unacceptable."
The company also said it would recommend simulator training for pilots before the 737 Max jets can return to service.
Calhoun also told CNBC on Wednesday he's confident that regulators will permit the 737 Max to return to service by the middle of 2020.
Last week, Boeing gave airlines and suppliers that same timetable, which was months later than the company previously expected.
— CNBC's Leslie Josephs contributed to this report.